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Autoensamblaje de polipéptidos α-hélicos en espirales microscópicas y enantiomórficas
Charlotte D Vacogne1,2, Chunxiang Wei2, Klaus Tauer2
1University of Potsdam , Institute of Chemistry , Karl-Liebknecht-Straße 24-25 , 14476 Potsdam , Germany.
Journal of the American Chemical Society
|August 11, 2018
Resumen
Los investigadores crearon partículas de polipéptido en espiral a partir de materiales bioinspirados. La quiralidad de las hélices alfa dictó la espiral
Área de la Ciencia:
- Ciencias de los materiales
- Biomateriales
- Química de los polímeros
Sus antecedentes:
- Las estructuras helicoidales son comunes en los materiales biológicos y cruciales para su función.
- La síntesis de materiales helicoidales bioinspirados que imitan la jerarquía natural es difícil.
Objetivo del estudio:
- Para informar de la primera síntesis de partículas polipéptidas que exhiben morfologías espirales.
- Investigar la relación entre la quiralidad alfa-helical y la formación de espirales macroscópicas.
Principales métodos:
- Emulsión directa de polipéptidos, específicamente de homo- y copolipéptidos alfa-hélicos de glutamato de gamma-bencilo y de alilglicina.
- Caracterización de la morfología y quiralidad de las partículas en estado seco.
Principales resultados:
- Las partículas de polipéptido sintetizadas muestran morfologías espirales en estado seco.
- La quiralidad de las hélices alfa controlaba directamente la quiralidad de las espirales observadas (por ejemplo, las hélices alfa de la derecha producían espirales en el sentido de las agujas del reloj).
- La alteración de la conformación alfa helicoidal condujo a la formación de espirales irregulares o suprimidas.
Conclusiones:
- Demostró un método para crear materiales helicoidales bioinspirados con quiralidad controlada.
- Propuso un mecanismo para la transmisión de helicidad y quiralidad desde niveles moleculares a jerárquicos a través de la agrupación de fibrillas.
- Abrió vías para el diseño de biomateriales helicoidales avanzados.
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